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author | Jeff Johnston <jjohnstn@redhat.com> | 2010-10-09 02:31:22 +0000 |
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committer | Jeff Johnston <jjohnstn@redhat.com> | 2010-10-09 02:31:22 +0000 |
commit | 4606798ea008ab8d3dcec4757198ac0294b46a6a (patch) | |
tree | 56d29e479378a315f9eeacff338571174681ca44 /libgloss/tic6x/sbrk.c | |
parent | cab874029f570d61eefbc8cbeb4fb74cc57a9457 (diff) | |
download | cygnal-4606798ea008ab8d3dcec4757198ac0294b46a6a.tar.gz cygnal-4606798ea008ab8d3dcec4757198ac0294b46a6a.tar.bz2 cygnal-4606798ea008ab8d3dcec4757198ac0294b46a6a.zip |
2010-10-08 Bernd Schmidt <bernds@codesourcery.com>
Joseph Myers <joseph@codesourcery.com>
* configure.in: Handle tic6x targets.
* configure: Regenerate.
* tic6x/Makefile.in, tic6x/configure.in, tic6x/crt0.S,
tic6x/getpid.c, tic6x/kill.c, tic6x/sbrk.c, tic6x/syscalls.c: New.
* tic6x/configure: New (generated).
Diffstat (limited to 'libgloss/tic6x/sbrk.c')
-rw-r--r-- | libgloss/tic6x/sbrk.c | 59 |
1 files changed, 59 insertions, 0 deletions
diff --git a/libgloss/tic6x/sbrk.c b/libgloss/tic6x/sbrk.c new file mode 100644 index 000000000..5bb645e3e --- /dev/null +++ b/libgloss/tic6x/sbrk.c @@ -0,0 +1,59 @@ +/* sbrk.c -- Implementation of the low-level sbrk() routine + * + * Copyright (c) 2004 National Semiconductor Corporation + * + * The authors hereby grant permission to use, copy, modify, distribute, + * and license this software and its documentation for any purpose, provided + * that existing copyright notices are retained in all copies and that this + * notice is included verbatim in any distributions. No written agreement, + * license, or royalty fee is required for any of the authorized uses. + * Modifications to this software may be copyrighted by their authors + * and need not follow the licensing terms described here, provided that + * the new terms are clearly indicated on the first page of each file where + * they apply. + */ + +#include <errno.h> +#include <stddef.h> /* where ptrdiff_t is defined */ +#include <stdlib.h> + +/* Start of the heap. */ +extern const char _HEAP_START __attribute__((section(".heap"))); +/* End of the heap (maximum value of heap_ptr). */ +extern const char _HEAP_MAX __attribute__((section(".heap"))); + +/* Extend heap space by size bytes. + Return start of new space allocated, or -1 for errors + Error cases: + 1. Allocation is not within heap range */ + +void * sbrk (ptrdiff_t size) +{ + /* + * The following two memory locations should be defined in the linker script file + */ + + static const char * heap_ptr; /* pointer to head of heap */ + const char * old_heap_ptr; + static unsigned char init_sbrk = 0; + + /* heap_ptr is initialized to HEAP_START */ + if (init_sbrk == 0) + { + heap_ptr = &_HEAP_START; + init_sbrk = 1; + } + + old_heap_ptr = heap_ptr; + + if ((heap_ptr + size) > &_HEAP_MAX) + { + /* top of heap is bigger than _HEAP_MAX */ + errno = ENOMEM; + return (void *) -1; + } + + /* success: update heap_ptr and return previous value */ + heap_ptr += size; + return (void *)old_heap_ptr; +} |